/**
 * \addtogroup apps
 * @{
 */

/**
 * \defgroup httpd Web server
 * @{
 * The uIP web server is a very simplistic implementation of an HTTP
 * server. It can serve web pages and files from a read-only ROM
 * filesystem, and provides a very small scripting language.

 */

/**
 * \file
 *         Web server
 * \author
 *         Adam Dunkels <adam@sics.se>
 */


/*
 * Copyright (c) 2004, Adam Dunkels.
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 3. Neither the name of the Institute nor the names of its contributors
 *    may be used to endorse or promote products derived from this software
 *    without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE INSTITUTE AND CONTRIBUTORS ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL THE INSTITUTE OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 *
 * This file is part of the uIP TCP/IP stack.
 *
 * Author: Adam Dunkels <adam@sics.se>
 *
 * $Id: httpd.c,v 1.2 2006/06/11 21:46:38 adam Exp $
 */

#include "uip.h"
#include "httpd.h"
#include "httpd-fs.h"
#include "httpd-cgi.h"
#include "http-strings.h"

#include <string.h>

#define STATE_WAITING 0
#define STATE_OUTPUT  1

#define ISO_nl      0x0a
#define ISO_space   0x20
#define ISO_bang    0x21
#define ISO_percent 0x25
#define ISO_period  0x2e
#define ISO_slash   0x2f
#define ISO_colon   0x3a


/*---------------------------------------------------------------------------*/
static unsigned short
generate_part_of_file(void* state)
{
	struct httpd_state* s = (struct httpd_state*)state;

	if(s->file.len > uip_mss()) {
		s->len = uip_mss();
	} else {
		s->len = s->file.len;
	}

	memcpy(uip_appdata, s->file.data, s->len);

	return s->len;
}
/*---------------------------------------------------------------------------*/
static
PT_THREAD(send_file(struct httpd_state* s))
{
	PSOCK_BEGIN(&s->sout);

	do {
		PSOCK_GENERATOR_SEND(&s->sout, generate_part_of_file, s);
		s->file.len -= s->len;
		s->file.data += s->len;
	} while(s->file.len > 0);

	PSOCK_END(&s->sout);
}
/*---------------------------------------------------------------------------*/
static
PT_THREAD(send_part_of_file(struct httpd_state* s))
{
	PSOCK_BEGIN(&s->sout);

	PSOCK_SEND(&s->sout, s->file.data, s->len);

	PSOCK_END(&s->sout);
}
/*---------------------------------------------------------------------------*/
static void
next_scriptstate(struct httpd_state* s)
{
	char* p;
	p = strchr(s->scriptptr, ISO_nl) + 1;
	s->scriptlen -= (unsigned short)(p - s->scriptptr);
	s->scriptptr = p;
}
/*---------------------------------------------------------------------------*/
static
PT_THREAD(handle_script(struct httpd_state* s))
{
	char* ptr;

	PT_BEGIN(&s->scriptpt);


	while(s->file.len > 0) {

		/* Check if we should start executing a script. */
		if(*s->file.data == ISO_percent &&
		        *(s->file.data + 1) == ISO_bang) {
			s->scriptptr = s->file.data + 3;
			s->scriptlen = s->file.len - 3;

			if(*(s->scriptptr - 1) == ISO_colon) {
				httpd_fs_open(s->scriptptr + 1, &s->file);
				PT_WAIT_THREAD(&s->scriptpt, send_file(s));
			} else {
				PT_WAIT_THREAD(&s->scriptpt,
				               httpd_cgi(s->scriptptr)(s, s->scriptptr));
			}

			next_scriptstate(s);

			/* The script is over, so we reset the pointers and continue
			sending the rest of the file. */
			s->file.data = s->scriptptr;
			s->file.len = s->scriptlen;
		} else {
			/* See if we find the start of script marker in the block of HTML
			to be sent. */

			if(s->file.len > uip_mss()) {
				s->len = uip_mss();
			} else {
				s->len = s->file.len;
			}

			if(*s->file.data == ISO_percent) {
				ptr = strchr(s->file.data + 1, ISO_percent);
			} else {
				ptr = strchr(s->file.data, ISO_percent);
			}

			if(ptr != NULL &&
			        ptr != s->file.data) {
				s->len = (int)(ptr - s->file.data);

				if(s->len >= uip_mss()) {
					s->len = uip_mss();
				}
			}

			PT_WAIT_THREAD(&s->scriptpt, send_part_of_file(s));
			s->file.data += s->len;
			s->file.len -= s->len;

		}
	}

	PT_END(&s->scriptpt);
}
/*---------------------------------------------------------------------------*/
static
PT_THREAD(send_headers(struct httpd_state* s, const char* statushdr))
{
	char* ptr;

	PSOCK_BEGIN(&s->sout);

	PSOCK_SEND_STR(&s->sout, statushdr);

	ptr = strrchr(s->filename, ISO_period);

	if(ptr == NULL) {
		PSOCK_SEND_STR(&s->sout, http_content_type_binary);
	} else if(strncmp(http_html, ptr, 5) == 0 ||
	          strncmp(http_shtml, ptr, 6) == 0) {
		PSOCK_SEND_STR(&s->sout, http_content_type_html);
	} else if(strncmp(http_css, ptr, 4) == 0) {
		PSOCK_SEND_STR(&s->sout, http_content_type_css);
	} else if(strncmp(http_png, ptr, 4) == 0) {
		PSOCK_SEND_STR(&s->sout, http_content_type_png);
	} else if(strncmp(http_gif, ptr, 4) == 0) {
		PSOCK_SEND_STR(&s->sout, http_content_type_gif);
	} else if(strncmp(http_jpg, ptr, 4) == 0) {
		PSOCK_SEND_STR(&s->sout, http_content_type_jpg);
	} else {
		PSOCK_SEND_STR(&s->sout, http_content_type_plain);
	}

	PSOCK_END(&s->sout);
}
/*---------------------------------------------------------------------------*/
static
PT_THREAD(handle_output(struct httpd_state* s))
{
	char* ptr;

	PT_BEGIN(&s->outputpt);

	if(!httpd_fs_open(s->filename, &s->file)) {
		httpd_fs_open(http_404_html, &s->file);
		strcpy(s->filename, http_404_html);
		PT_WAIT_THREAD(&s->outputpt,
		               send_headers(s,
		                            http_header_404));
		PT_WAIT_THREAD(&s->outputpt,
		               send_file(s));
	} else {
		PT_WAIT_THREAD(&s->outputpt,
		               send_headers(s,
		                            http_header_200));
		ptr = strchr(s->filename, ISO_period);

		if(ptr != NULL && strncmp(ptr, http_shtml, 6) == 0) {
			PT_INIT(&s->scriptpt);
			PT_WAIT_THREAD(&s->outputpt, handle_script(s));
		} else {
			PT_WAIT_THREAD(&s->outputpt,
			               send_file(s));
		}
	}

	PSOCK_CLOSE(&s->sout);
	PT_END(&s->outputpt);
}
/*---------------------------------------------------------------------------*/
static
PT_THREAD(handle_input(struct httpd_state* s))
{
	PSOCK_BEGIN(&s->sin);

	PSOCK_READTO(&s->sin, ISO_space);


	if(strncmp(s->inputbuf, http_get, 4) != 0) {
		PSOCK_CLOSE_EXIT(&s->sin);
	}

	PSOCK_READTO(&s->sin, ISO_space);

	if(s->inputbuf[0] != ISO_slash) {
		PSOCK_CLOSE_EXIT(&s->sin);
	}

	if(s->inputbuf[1] == ISO_space) {
		strncpy(s->filename, http_index_html, sizeof(s->filename));
	} else {
		s->inputbuf[PSOCK_DATALEN(&s->sin) - 1] = 0;
		strncpy(s->filename, &s->inputbuf[0], sizeof(s->filename));
	}

	/*  httpd_log_file(uip_conn->ripaddr, s->filename);*/

	s->state = STATE_OUTPUT;

	while(1) {
		PSOCK_READTO(&s->sin, ISO_nl);

		if(strncmp(s->inputbuf, http_referer, 8) == 0) {
			s->inputbuf[PSOCK_DATALEN(&s->sin) - 2] = 0;
			/*      httpd_log(&s->inputbuf[9]);*/
		}
	}

	PSOCK_END(&s->sin);
}
/*---------------------------------------------------------------------------*/
static void
handle_connection(struct httpd_state* s)
{
	handle_input(s);

	if(s->state == STATE_OUTPUT) {
		handle_output(s);
	}
}
/*---------------------------------------------------------------------------*/
void
httpd_appcall(void)
{
	struct httpd_state* s = (struct httpd_state*) & (uip_conn->appstate);

	if(uip_closed() || uip_aborted() || uip_timedout()) {
	} else if(uip_connected()) {
		PSOCK_INIT(&s->sin, s->inputbuf, sizeof(s->inputbuf) - 1);
		PSOCK_INIT(&s->sout, s->inputbuf, sizeof(s->inputbuf) - 1);
		PT_INIT(&s->outputpt);
		s->state = STATE_WAITING;
		/*    timer_set(&s->timer, CLOCK_SECOND * 100);*/
		s->timer = 0;
		handle_connection(s);
	} else if(s != NULL) {
		if(uip_poll()) {
			++s->timer;

			if(s->timer >= 20) {
				uip_abort();
			}
		} else {
			s->timer = 0;
		}

		handle_connection(s);
	} else {
		uip_abort();
	}
}
/*---------------------------------------------------------------------------*/
/**
 * \brief      Initialize the web server
 *
 *             This function initializes the web server and should be
 *             called at system boot-up.
 */
void
httpd_init(void)
{
	uip_listen(HTONS(80));
}
/*---------------------------------------------------------------------------*/
/** @} */
